Section 3

In chloroplast, converting light energy into echmical energy
6CO2 + 6H2O -> C6H12O6 + 6O2

Waxy cuticle - reduce water evaportation
Palisade layer - chloroplast, photosynthesis
Upper epidermis - transperent, let light in
Spongy - air spaces for gas exchange
Broad - large SA
Vascular Bundle - transport water, nutrients

Limiting factor - factors that is lacking
Light, CO2 level, Temperature

Dunk leaf in boiling water, stops chemical reactions. put leaf in ethanol, heat in water bath until boils, gets rid of chlorphyll. Rinse eaf with water add iodine solution . In presence of starch orange to blue black

Chlorophyll
Use variegated leaf that is exposed to light, record white and green bits, Test for starch, green bits turn blue black white parts don't because only green contains chlorophyll and produces starch

Keep plant in a jar that has soda lime (to absorb CO2) then test for starch won't turn blue black. Shows no starch is made, CO2 needed for photosynthesis

Plant that has been grown without any light for 48 hrs, plants has used up the starch stres, test leaf for starch won't turn blue black

pondweed in test tube that has water and sodium hydrgoencarbonate for CO2, attach to capillary tibe and a syyringe Place light source at 10 cm distance, pondweed left to photosynthesis, oxygen collected in capillary tube gas vol measured from syringe. Increase distance of light. Can be used for temp and CO2 conc

Nitrates - nitrogen makes amino acids and protein, needed for cell growth. Stunted/leaves turn yellow
Phosphates: making DNA, cell membranes, resp, grwth. Poor root growth/leaves purple
Potassium: for enzymes needed for photo and resp. Poor flower,fruit growth/discolored leaf.
Magnesium: making chlorophyll/ yellow leaves

Xylem: water, mineral salts from roots to the shoots in the transpiration stream
Phloem: transport sucrose, amino acids from leaves to other parts - tranlocation

taken up by osmosis, from high conc in soil to low conc in root cells
Big SA for absorbing water

Evaporation of water from plant's surface. Water drawn up by xylem evaporates from the leaf

Light: Higher light intesnsity, faster rate of transp, stomata close in dark, water cant escape
Temp: higher temp, faster rate,particles have more energy to evaporate
Wind: higher wind speed, faster rate, moves water particles around the leaf away, creating big conc difference
Humidity: less humid, faster rate, less water particles around the lea, big conc grandeint

Potometer apparatus, cut shoot put in and close with bung, watertight, airtightremve end of tube from beaker of water until air bubble forms then put back in water. Measure starting position of bubble, start stopwatch, measure dstance moved

Light: use lamp and cupboard
Temp: Increase, decrease temp of room
Humidity: increase humidity by spraying water in plastic bag and seal around plant
Wind speed: use fan and no fan